One li equals 10 hao, 1/10 of a fen, 1/1000 of a chi, or 1/3 mm in China.
[1] [2] This law of length measurement was issued by the Chinese government in 1929, and has been effective since 1 January, 1930.
The base unit chi is defined to be 1/3 meter.
The Chinese word for metre is 米 mǐ, which can take the Chinese standard SI prefixes (for "kilo-", "centi-", etc.).
A kilometre, however, may also be called 公里 gōnglǐ, i.e. a metric lǐ.